[IA64-SGI] altix: tioca chip driver (agp)

Provide a driver for the altix TIOCA AGP chipset.  An agpgart backend will
be provided as a separate patch.

Signed-off-by: Mark Maule <maule@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

3 files changed, 671 insertions, 1 deletions

diff --git a/arch/ia64/sn/kernel/io_init.c b/arch/ia64/sn/kernel/io_init.c
index 9f9d0464f72c..18160a06a8c9 100644
--- a/arch/ia64/sn/kernel/io_init.c
+++ b/arch/ia64/sn/kernel/io_init.c
@@ -19,6 +19,7 @@
 #include "xtalk/hubdev.h"
 #include <asm/sn/io.h>
 #include <asm/sn/simulator.h>
+#include <asm/sn/tioca_provider.h>
 
 char master_baseio_wid;
 nasid_t master_nasid = INVALID_NASID;   /* Partition Master */
@@ -393,6 +394,7 @@ static int __init sn_pci_init(void)
                 sn_pci_provider[i] = &sn_pci_default_provider;
 
         pcibr_init_provider();
+        tioca_init_provider();
 
         /*
          * This is needed to avoid bounce limit checks in the blk layer
diff --git a/arch/ia64/sn/pci/Makefile b/arch/ia64/sn/pci/Makefile
index b5dca0097a8e..2f915bce25f9 100644
--- a/arch/ia64/sn/pci/Makefile
+++ b/arch/ia64/sn/pci/Makefile
@@ -7,4 +7,4 @@
 #
 # Makefile for the sn pci general routines.
 
-obj-y := pci_dma.o pcibr/ 
+obj-y := pci_dma.o tioca_provider.o pcibr/ 
diff --git a/arch/ia64/sn/pci/tioca_provider.c b/arch/ia64/sn/pci/tioca_provider.c
new file mode 100644
index 000000000000..2234d61cdd4b
--- /dev/null
+++ b/arch/ia64/sn/pci/tioca_provider.c
@@ -0,0 +1,668 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2003-2005 Silicon Graphics, Inc.  All Rights Reserved.
+ */
+
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <asm/sn/sn_sal.h>
+#include <asm/sn/addrs.h>
+#include <asm/sn/pcidev.h>
+#include <asm/sn/pcibus_provider_defs.h>
+#include <asm/sn/tioca_provider.h>
+
+uint32_t tioca_gart_found;
+EXPORT_SYMBOL(tioca_gart_found);        /* used by agp-sgi */
+
+LIST_HEAD(tioca_list);
+EXPORT_SYMBOL(tioca_list);      /* used by agp-sgi */
+
+static int tioca_gart_init(struct tioca_kernel *);
+
+/**
+ * tioca_gart_init - Initialize SGI TIOCA GART
+ * @tioca_common: ptr to common prom/kernel struct identifying the 
+ *
+ * If the indicated tioca has devices present, initialize its associated
+ * GART MMR's and kernel memory.
+ */
+static int
+tioca_gart_init(struct tioca_kernel *tioca_kern)
+{
+        uint64_t ap_reg;
+        uint64_t offset;
+        struct page *tmp;
+        struct tioca_common *tioca_common;
+        volatile struct tioca *ca_base;
+
+        tioca_common = tioca_kern->ca_common;
+        ca_base = (struct tioca *)tioca_common->ca_common.bs_base;
+
+        if (list_empty(tioca_kern->ca_devices))
+                return 0;
+
+        ap_reg = 0;
+
+        /*
+         * Validate aperature size
+         */
+
+        switch (CA_APERATURE_SIZE >> 20) {
+        case 4:
+                ap_reg |= (0x3ff << CA_GART_AP_SIZE_SHFT);      /* 4MB */
+                break;
+        case 8:
+                ap_reg |= (0x3fe << CA_GART_AP_SIZE_SHFT);      /* 8MB */
+                break;
+        case 16:
+                ap_reg |= (0x3fc << CA_GART_AP_SIZE_SHFT);      /* 16MB */
+                break;
+        case 32:
+                ap_reg |= (0x3f8 << CA_GART_AP_SIZE_SHFT);      /* 32 MB */
+                break;
+        case 64:
+                ap_reg |= (0x3f0 << CA_GART_AP_SIZE_SHFT);      /* 64 MB */
+                break;
+        case 128:
+                ap_reg |= (0x3e0 << CA_GART_AP_SIZE_SHFT);      /* 128 MB */
+                break;
+        case 256:
+                ap_reg |= (0x3c0 << CA_GART_AP_SIZE_SHFT);      /* 256 MB */
+                break;
+        case 512:
+                ap_reg |= (0x380 << CA_GART_AP_SIZE_SHFT);      /* 512 MB */
+                break;
+        case 1024:
+                ap_reg |= (0x300 << CA_GART_AP_SIZE_SHFT);      /* 1GB */
+                break;
+        case 2048:
+                ap_reg |= (0x200 << CA_GART_AP_SIZE_SHFT);      /* 2GB */
+                break;
+        case 4096:
+                ap_reg |= (0x000 << CA_GART_AP_SIZE_SHFT);      /* 4 GB */
+                break;
+        default:
+                printk(KERN_ERR "%s:  Invalid CA_APERATURE_SIZE "
+                       "0x%lx\n", __FUNCTION__, (ulong) CA_APERATURE_SIZE);
+                return -1;
+        }
+
+        /*
+         * Set up other aperature parameters
+         */
+
+        if (PAGE_SIZE >= 16384) {
+                tioca_kern->ca_ap_pagesize = 16384;
+                ap_reg |= CA_GART_PAGE_SIZE;
+        } else {
+                tioca_kern->ca_ap_pagesize = 4096;
+        }
+
+        tioca_kern->ca_ap_size = CA_APERATURE_SIZE;
+        tioca_kern->ca_ap_bus_base = CA_APERATURE_BASE;
+        tioca_kern->ca_gart_entries =
+            tioca_kern->ca_ap_size / tioca_kern->ca_ap_pagesize;
+
+        ap_reg |= (CA_GART_AP_ENB_AGP | CA_GART_AP_ENB_PCI);
+        ap_reg |= tioca_kern->ca_ap_bus_base;
+
+        /*
+         * Allocate and set up the GART
+         */
+
+        tioca_kern->ca_gart_size = tioca_kern->ca_gart_entries * sizeof(u64);
+        tmp =
+            alloc_pages_node(tioca_kern->ca_closest_node,
+                             GFP_KERNEL | __GFP_ZERO,
+                             get_order(tioca_kern->ca_gart_size));
+
+        if (!tmp) {
+                printk(KERN_ERR "%s:  Could not allocate "
+                       "%lu bytes (order %d) for GART\n",
+                       __FUNCTION__,
+                       tioca_kern->ca_gart_size,
+                       get_order(tioca_kern->ca_gart_size));
+                return -ENOMEM;
+        }
+
+        tioca_kern->ca_gart = page_address(tmp);
+        tioca_kern->ca_gart_coretalk_addr =
+            PHYS_TO_TIODMA(virt_to_phys(tioca_kern->ca_gart));
+
+        /*
+         * Compute PCI/AGP convenience fields 
+         */
+
+        offset = CA_PCI32_MAPPED_BASE - CA_APERATURE_BASE;
+        tioca_kern->ca_pciap_base = CA_PCI32_MAPPED_BASE;
+        tioca_kern->ca_pciap_size = CA_PCI32_MAPPED_SIZE;
+        tioca_kern->ca_pcigart_start = offset / tioca_kern->ca_ap_pagesize;
+        tioca_kern->ca_pcigart_base =
+            tioca_kern->ca_gart_coretalk_addr + offset;
+        tioca_kern->ca_pcigart =
+            &tioca_kern->ca_gart[tioca_kern->ca_pcigart_start];
+        tioca_kern->ca_pcigart_entries =
+            tioca_kern->ca_pciap_size / tioca_kern->ca_ap_pagesize;
+        tioca_kern->ca_pcigart_pagemap =
+            kcalloc(1, tioca_kern->ca_pcigart_entries / 8, GFP_KERNEL);
+        if (!tioca_kern->ca_pcigart_pagemap) {
+                free_pages((unsigned long)tioca_kern->ca_gart,
+                           get_order(tioca_kern->ca_gart_size));
+                return -1;
+        }
+
+        offset = CA_AGP_MAPPED_BASE - CA_APERATURE_BASE;
+        tioca_kern->ca_gfxap_base = CA_AGP_MAPPED_BASE;
+        tioca_kern->ca_gfxap_size = CA_AGP_MAPPED_SIZE;
+        tioca_kern->ca_gfxgart_start = offset / tioca_kern->ca_ap_pagesize;
+        tioca_kern->ca_gfxgart_base =
+            tioca_kern->ca_gart_coretalk_addr + offset;
+        tioca_kern->ca_gfxgart =
+            &tioca_kern->ca_gart[tioca_kern->ca_gfxgart_start];
+        tioca_kern->ca_gfxgart_entries =
+            tioca_kern->ca_gfxap_size / tioca_kern->ca_ap_pagesize;
+
+        /*
+         * various control settings:
+         *      use agp op-combining
+         *      use GET semantics to fetch memory
+         *      participate in coherency domain
+         *      prefetch TLB entries
+         */
+
+        ca_base->ca_control1 |= CA_AGPDMA_OP_ENB_COMBDELAY;     /* PV895469 ? */
+        ca_base->ca_control2 &= ~(CA_GART_MEM_PARAM);
+        ca_base->ca_control2 |= (0x2ull << CA_GART_MEM_PARAM_SHFT);
+        tioca_kern->ca_gart_iscoherent = 1;
+        ca_base->ca_control2 |=
+            (CA_GART_WR_PREFETCH_ENB | CA_GART_RD_PREFETCH_ENB);
+
+        /*
+         * Unmask GART fetch error interrupts.  Clear residual errors first.
+         */
+
+        ca_base->ca_int_status_alias = CA_GART_FETCH_ERR;
+        ca_base->ca_mult_error_alias = CA_GART_FETCH_ERR;
+        ca_base->ca_int_mask &= ~CA_GART_FETCH_ERR;
+
+        /*
+         * Program the aperature and gart registers in TIOCA
+         */
+
+        ca_base->ca_gart_aperature = ap_reg;
+        ca_base->ca_gart_ptr_table = tioca_kern->ca_gart_coretalk_addr | 1;
+
+        return 0;
+}
+
+/**
+ * tioca_fastwrite_enable - enable AGP FW for a tioca and its functions
+ * @tioca_kernel: structure representing the CA
+ *
+ * Given a CA, scan all attached functions making sure they all support
+ * FastWrite.  If so, enable FastWrite for all functions and the CA itself.
+ */
+
+void
+tioca_fastwrite_enable(struct tioca_kernel *tioca_kern)
+{
+        int cap_ptr;
+        uint64_t ca_control1;
+        uint32_t reg;
+        struct tioca *tioca_base;
+        struct pci_dev *pdev;
+        struct tioca_common *common;
+
+        common = tioca_kern->ca_common;
+
+        /*
+         * Scan all vga controllers on this bus making sure they all
+         * suport FW.  If not, return.
+         */
+
+        list_for_each_entry(pdev, tioca_kern->ca_devices, bus_list) {
+                if (pdev->class != (PCI_CLASS_DISPLAY_VGA << 8))
+                        continue;
+
+                cap_ptr = pci_find_capability(pdev, PCI_CAP_ID_AGP);
+                if (!cap_ptr)
+                        return; /* no AGP CAP means no FW */
+
+                pci_read_config_dword(pdev, cap_ptr + PCI_AGP_STATUS, &reg);
+                if (!(reg & PCI_AGP_STATUS_FW))
+                        return; /* function doesn't support FW */
+        }
+
+        /*
+         * Set fw for all vga fn's
+         */
+
+        list_for_each_entry(pdev, tioca_kern->ca_devices, bus_list) {
+                if (pdev->class != (PCI_CLASS_DISPLAY_VGA << 8))
+                        continue;
+
+                cap_ptr = pci_find_capability(pdev, PCI_CAP_ID_AGP);
+                pci_read_config_dword(pdev, cap_ptr + PCI_AGP_COMMAND, &reg);
+                reg |= PCI_AGP_COMMAND_FW;
+                pci_write_config_dword(pdev, cap_ptr + PCI_AGP_COMMAND, reg);
+        }
+
+        /*
+         * Set ca's fw to match
+         */
+
+        tioca_base = (struct tioca *)common->ca_common.bs_base;
+        ca_control1 = tioca_base->ca_control1;
+        ca_control1 |= CA_AGP_FW_ENABLE;
+        tioca_base->ca_control1 = ca_control1;
+}
+
+EXPORT_SYMBOL(tioca_fastwrite_enable);  /* used by agp-sgi */
+
+/**
+ * tioca_dma_d64 - create a DMA mapping using 64-bit direct mode
+ * @paddr: system physical address
+ *
+ * Map @paddr into 64-bit CA bus space.  No device context is necessary.
+ * Bits 53:0 come from the coretalk address.  We just need to mask in the
+ * following optional bits of the 64-bit pci address:
+ *
+ * 63:60 - Coretalk Packet Type -  0x1 for Mem Get/Put (coherent)
+ *                                 0x2 for PIO (non-coherent)
+ *                                 We will always use 0x1
+ * 55:55 - Swap bytes              Currently unused
+ */
+static uint64_t
+tioca_dma_d64(unsigned long paddr)
+{
+        dma_addr_t bus_addr;
+
+        bus_addr = PHYS_TO_TIODMA(paddr);
+
+        BUG_ON(!bus_addr);
+        BUG_ON(bus_addr >> 54);
+
+        /* Set upper nibble to Cache Coherent Memory op */
+        bus_addr |= (1UL << 60);
+
+        return bus_addr;
+}
+
+/**
+ * tioca_dma_d48 - create a DMA mapping using 48-bit direct mode
+ * @pdev: linux pci_dev representing the function
+ * @paddr: system physical address
+ *
+ * Map @paddr into 64-bit bus space of the CA associated with @pcidev_info.
+ *
+ * The CA agp 48 bit direct address falls out as follows:
+ *
+ * When direct mapping AGP addresses, the 48 bit AGP address is
+ * constructed as follows:
+ *
+ * [47:40] - Low 8 bits of the page Node ID extracted from coretalk
+ *              address [47:40].  The upper 8 node bits are fixed
+ *              and come from the xxx register bits [5:0]
+ * [39:38] - Chiplet ID extracted from coretalk address [39:38]
+ * [37:00] - node offset extracted from coretalk address [37:00]
+ * 
+ * Since the node id in general will be non-zero, and the chiplet id
+ * will always be non-zero, it follows that the device must support
+ * a dma mask of at least 0xffffffffff (40 bits) to target node 0
+ * and in general should be 0xffffffffffff (48 bits) to target nodes
+ * up to 255.  Nodes above 255 need the support of the xxx register,
+ * and so a given CA can only directly target nodes in the range
+ * xxx - xxx+255.
+ */
+static uint64_t
+tioca_dma_d48(struct pci_dev *pdev, uint64_t paddr)
+{
+        struct tioca_common *tioca_common;
+        struct tioca *ca_base;
+        uint64_t ct_addr;
+        dma_addr_t bus_addr;
+        uint32_t node_upper;
+        uint64_t agp_dma_extn;
+        struct pcidev_info *pcidev_info = SN_PCIDEV_INFO(pdev);
+
+        tioca_common = (struct tioca_common *)pcidev_info->pdi_pcibus_info;
+        ca_base = (struct tioca *)tioca_common->ca_common.bs_base;
+
+        ct_addr = PHYS_TO_TIODMA(paddr);
+        if (!ct_addr)
+                return 0;
+
+        bus_addr = (dma_addr_t) (ct_addr & 0xffffffffffff);
+        node_upper = ct_addr >> 48;
+
+        if (node_upper > 64) {
+                printk(KERN_ERR "%s:  coretalk addr 0x%p node id out "
+                       "of range\n", __FUNCTION__, (void *)ct_addr);
+                return 0;
+        }
+
+        agp_dma_extn = ca_base->ca_agp_dma_addr_extn;
+        if (node_upper != (agp_dma_extn >> CA_AGP_DMA_NODE_ID_SHFT)) {
+                printk(KERN_ERR "%s:  coretalk upper node (%u) "
+                       "mismatch with ca_agp_dma_addr_extn (%lu)\n",
+                       __FUNCTION__,
+                       node_upper, (agp_dma_extn >> CA_AGP_DMA_NODE_ID_SHFT));
+                return 0;
+        }
+
+        return bus_addr;
+}
+
+/**
+ * tioca_dma_mapped - create a DMA mapping using a CA GART 
+ * @pdev: linux pci_dev representing the function
+ * @paddr: host physical address to map
+ * @req_size: len (bytes) to map
+ *
+ * Map @paddr into CA address space using the GART mechanism.  The mapped
+ * dma_addr_t is guarenteed to be contiguous in CA bus space.
+ */
+static dma_addr_t
+tioca_dma_mapped(struct pci_dev *pdev, uint64_t paddr, size_t req_size)
+{
+        int i, ps, ps_shift, entry, entries, mapsize, last_entry;
+        uint64_t xio_addr, end_xio_addr;
+        struct tioca_common *tioca_common;
+        struct tioca_kernel *tioca_kern;
+        dma_addr_t bus_addr = 0;
+        struct tioca_dmamap *ca_dmamap;
+        void *map;
+        unsigned long flags;
+        struct pcidev_info *pcidev_info = SN_PCIDEV_INFO(pdev);;
+
+        tioca_common = (struct tioca_common *)pcidev_info->pdi_pcibus_info;
+        tioca_kern = (struct tioca_kernel *)tioca_common->ca_kernel_private;
+
+        xio_addr = PHYS_TO_TIODMA(paddr);
+        if (!xio_addr)
+                return 0;
+
+        spin_lock_irqsave(&tioca_kern->ca_lock, flags);
+
+        /*
+         * allocate a map struct
+         */
+
+        ca_dmamap = kcalloc(1, sizeof(struct tioca_dmamap), GFP_ATOMIC);
+        if (!ca_dmamap)
+                goto map_return;
+
+        /*
+         * Locate free entries that can hold req_size.  Account for
+         * unaligned start/length when allocating.
+         */
+
+        ps = tioca_kern->ca_ap_pagesize;        /* will be power of 2 */
+        ps_shift = ffs(ps) - 1;
+        end_xio_addr = xio_addr + req_size - 1;
+
+        entries = (end_xio_addr >> ps_shift) - (xio_addr >> ps_shift) + 1;
+
+        map = tioca_kern->ca_pcigart_pagemap;
+        mapsize = tioca_kern->ca_pcigart_entries;
+
+        entry = find_first_zero_bit(map, mapsize);
+        while (entry < mapsize) {
+                last_entry = find_next_bit(map, mapsize, entry);
+
+                if (last_entry - entry >= entries)
+                        break;
+
+                entry = find_next_zero_bit(map, mapsize, last_entry);
+        }
+
+        if (entry > mapsize)
+                goto map_return;
+
+        for (i = 0; i < entries; i++)
+                set_bit(entry + i, map);
+
+        bus_addr = tioca_kern->ca_pciap_base + (entry * ps);
+
+        ca_dmamap->cad_dma_addr = bus_addr;
+        ca_dmamap->cad_gart_size = entries;
+        ca_dmamap->cad_gart_entry = entry;
+        list_add(&ca_dmamap->cad_list, &tioca_kern->ca_list);
+
+        if (xio_addr % ps) {
+                tioca_kern->ca_pcigart[entry] = tioca_paddr_to_gart(xio_addr);
+                bus_addr += xio_addr & (ps - 1);
+                xio_addr &= ~(ps - 1);
+                xio_addr += ps;
+                entry++;
+        }
+
+        while (xio_addr < end_xio_addr) {
+                tioca_kern->ca_pcigart[entry] = tioca_paddr_to_gart(xio_addr);
+                xio_addr += ps;
+                entry++;
+        }
+
+        tioca_tlbflush(tioca_kern);
+
+map_return:
+        spin_unlock_irqrestore(&tioca_kern->ca_lock, flags);
+        return bus_addr;
+}
+
+/**
+ * tioca_dma_unmap - release CA mapping resources
+ * @pdev: linux pci_dev representing the function
+ * @bus_addr: bus address returned by an earlier tioca_dma_map
+ * @dir: mapping direction (unused)
+ *
+ * Locate mapping resources associated with @bus_addr and release them.
+ * For mappings created using the direct modes (64 or 48) there are no
+ * resources to release.
+ */
+void
+tioca_dma_unmap(struct pci_dev *pdev, dma_addr_t bus_addr, int dir)
+{
+        int i, entry;
+        struct tioca_common *tioca_common;
+        struct tioca_kernel *tioca_kern;
+        struct tioca_dmamap *map;
+        struct pcidev_info *pcidev_info = SN_PCIDEV_INFO(pdev);
+        unsigned long flags;
+
+        tioca_common = (struct tioca_common *)pcidev_info->pdi_pcibus_info;
+        tioca_kern = (struct tioca_kernel *)tioca_common->ca_kernel_private;
+
+        /* return straight away if this isn't be a mapped address */
+
+        if (bus_addr < tioca_kern->ca_pciap_base ||
+            bus_addr >= (tioca_kern->ca_pciap_base + tioca_kern->ca_pciap_size))
+                return;
+
+        spin_lock_irqsave(&tioca_kern->ca_lock, flags);
+
+        list_for_each_entry(map, &tioca_kern->ca_dmamaps, cad_list)
+            if (map->cad_dma_addr == bus_addr)
+                break;
+
+        BUG_ON(map == NULL);
+
+        entry = map->cad_gart_entry;
+
+        for (i = 0; i < map->cad_gart_size; i++, entry++) {
+                clear_bit(entry, tioca_kern->ca_pcigart_pagemap);
+                tioca_kern->ca_pcigart[entry] = 0;
+        }
+        tioca_tlbflush(tioca_kern);
+
+        list_del(&map->cad_list);
+        spin_unlock_irqrestore(&tioca_kern->ca_lock, flags);
+        kfree(map);
+}
+
+/**
+ * tioca_dma_map - map pages for PCI DMA
+ * @pdev: linux pci_dev representing the function
+ * @paddr: host physical address to map
+ * @byte_count: bytes to map
+ *
+ * This is the main wrapper for mapping host physical pages to CA PCI space.
+ * The mapping mode used is based on the devices dma_mask.  As a last resort
+ * use the GART mapped mode.
+ */
+uint64_t
+tioca_dma_map(struct pci_dev *pdev, uint64_t paddr, size_t byte_count)
+{
+        uint64_t mapaddr;
+
+        /*
+         * If card is 64 or 48 bit addresable, use a direct mapping.  32
+         * bit direct is so restrictive w.r.t. where the memory resides that
+         * we don't use it even though CA has some support.
+         */
+
+        if (pdev->dma_mask == ~0UL)
+                mapaddr = tioca_dma_d64(paddr);
+        else if (pdev->dma_mask == 0xffffffffffffUL)
+                mapaddr = tioca_dma_d48(pdev, paddr);
+        else
+                mapaddr = 0;
+
+        /* Last resort ... use PCI portion of CA GART */
+
+        if (mapaddr == 0)
+                mapaddr = tioca_dma_mapped(pdev, paddr, byte_count);
+
+        return mapaddr;
+}
+
+/**
+ * tioca_error_intr_handler - SGI TIO CA error interrupt handler
+ * @irq: unused
+ * @arg: pointer to tioca_common struct for the given CA
+ * @pt: unused
+ *
+ * Handle a CA error interrupt.  Simply a wrapper around a SAL call which
+ * defers processing to the SGI prom.
+ */
+static irqreturn_t
+tioca_error_intr_handler(int irq, void *arg, struct pt_regs *pt)
+{
+        struct tioca_common *soft = arg;
+        struct ia64_sal_retval ret_stuff;
+        uint64_t segment;
+        uint64_t busnum;
+        ret_stuff.status = 0;
+        ret_stuff.v0 = 0;
+
+        segment = 0;
+        busnum = soft->ca_common.bs_persist_busnum;
+
+        SAL_CALL_NOLOCK(ret_stuff,
+                        (u64) SN_SAL_IOIF_ERROR_INTERRUPT,
+                        segment, busnum, 0, 0, 0, 0, 0);
+
+        return IRQ_HANDLED;
+}
+
+/**
+ * tioca_bus_fixup - perform final PCI fixup for a TIO CA bus
+ * @prom_bussoft: Common prom/kernel struct representing the bus
+ *
+ * Replicates the tioca_common pointed to by @prom_bussoft in kernel
+ * space.  Allocates and initializes a kernel-only area for a given CA,
+ * and sets up an irq for handling CA error interrupts.
+ *
+ * On successful setup, returns the kernel version of tioca_common back to
+ * the caller.
+ */
+void *
+tioca_bus_fixup(struct pcibus_bussoft *prom_bussoft)
+{
+        struct tioca_common *tioca_common;
+        struct tioca_kernel *tioca_kern;
+        struct pci_bus *bus;
+
+        /* sanity check prom rev */
+
+        if (sn_sal_rev_major() < 4 ||
+            (sn_sal_rev_major() == 4 && sn_sal_rev_minor() < 6)) {
+                printk
+                    (KERN_ERR "%s:  SGI prom rev 4.06 or greater required "
+                     "for tioca support\n", __FUNCTION__);
+                return NULL;
+        }
+
+        /*
+         * Allocate kernel bus soft and copy from prom.
+         */
+
+        tioca_common = kcalloc(1, sizeof(struct tioca_common), GFP_KERNEL);
+        if (!tioca_common)
+                return NULL;
+
+        memcpy(tioca_common, prom_bussoft, sizeof(struct tioca_common));
+        tioca_common->ca_common.bs_base |= __IA64_UNCACHED_OFFSET;
+
+        /* init kernel-private area */
+
+        tioca_kern = kcalloc(1, sizeof(struct tioca_kernel), GFP_KERNEL);
+        if (!tioca_kern) {
+                kfree(tioca_common);
+                return NULL;
+        }
+
+        tioca_kern->ca_common = tioca_common;
+        spin_lock_init(&tioca_kern->ca_lock);
+        INIT_LIST_HEAD(&tioca_kern->ca_dmamaps);
+        tioca_kern->ca_closest_node =
+            nasid_to_cnodeid(tioca_common->ca_closest_nasid);
+        tioca_common->ca_kernel_private = (uint64_t) tioca_kern;
+
+        bus = pci_find_bus(0, tioca_common->ca_common.bs_persist_busnum);
+        BUG_ON(!bus);
+        tioca_kern->ca_devices = &bus->devices;
+
+        /* init GART */
+
+        if (tioca_gart_init(tioca_kern) < 0) {
+                kfree(tioca_kern);
+                kfree(tioca_common);
+                return NULL;
+        }
+
+        tioca_gart_found++;
+        list_add(&tioca_kern->ca_list, &tioca_list);
+
+        if (request_irq(SGI_TIOCA_ERROR,
+                        tioca_error_intr_handler,
+                        SA_SHIRQ, "TIOCA error", (void *)tioca_common))
+                printk(KERN_WARNING
+                       "%s:  Unable to get irq %d.  "
+                       "Error interrupts won't be routed for TIOCA bus %d\n",
+                       __FUNCTION__, SGI_TIOCA_ERROR,
+                       (int)tioca_common->ca_common.bs_persist_busnum);
+
+        return tioca_common;
+}
+
+static struct sn_pcibus_provider tioca_pci_interfaces = {
+        .dma_map = tioca_dma_map,
+        .dma_map_consistent = tioca_dma_map,
+        .dma_unmap = tioca_dma_unmap,
+        .bus_fixup = tioca_bus_fixup,
+};
+
+/**
+ * tioca_init_provider - init SN PCI provider ops for TIO CA
+ */
+int
+tioca_init_provider(void)
+{
+        sn_pci_provider[PCIIO_ASIC_TYPE_TIOCA] = &tioca_pci_interfaces;
+        return 0;
+}